Machine tool



4 Sheets-Sheet l H. R. WILSON MACHINE from.

Aug. 14, 1951 Filed-Dec.

Aug. 14, 1951 H. R. WILSON 2,564,350

MACHINE TOOL Filed Dec. 5, 1946 4 Sheets-Sheet 2 INVENTOR.

Allg. 14, HR` W|| SON 2,564,350

MACHINE TOOL Filed Dec. 5, 1946 4 Sheets-Sheet 3 fi/z $4 k M f f6 45 JZZ J INVENTOR.

Aug. 14, 1951 H, R. WlLSON 2,564,350

MACHINE TOOL Filed Deo. 5, 1946 4 sheets-sheet 4 /Zg/ INVENToR.

Patented Aug. 14, 1951 MACHINE TOOL Harry Wilson, Waterloo, Iowa,assignor, by mesne assignments, to Skilsaw, Inc., Chicago, Ill., acorporation of Delaware Application December 3, 1946, Serial No. 713,615

3 Claims.

The present invention relates to improvements in a machine tool, andmore particularly to a machine tool of the radial saw type.

Machines of this type have been manufactured and sold heretofore forvarious woodworking and metal cutting applications. By changing thecutting tool, and with proper adjustment, such numerous operations canbe performed that the machines have been sold and used as havingpractically the facilities of a complete woodworking shop. With a sawblade an operator can rip, crosscut or mitre. Dadoing, gaining,ploughing, beveling,v iiuting, grooving may be performed by othercutting tools while still others will permit routing, shaping, copingandl cut-olfand tenoning.y Because of their Versatility they are ingreat demand today-especiallyv for the tremendous amount of home andfactoryconstruction now being undertaken.

Normally the arm of the operator is used to move the work unit backandforth across the work so there is still fatigueinvolved in theopera-tion of this type `of machine although the output of the operatoris tremendously increased. The various adjustments of the presentmachines are not too easily reached nor quickly made without time andenergy Aconsuming manipulations and the possibility that the'machine maybe me.- Achanically forced out of accurate alignment.` There are-certaininherent dangers in operating any tool. 4Safety guards commonly arethought ofr'as anuisance and are not used by the worker for hisprotection, or are removed by him because they partially block goodvisibility of the work and add friction to hand operation as they dragover or impinge upon the work. When ripping with a tool of the presenttype in green wood or if a knot is struck, the piece of wood may tend tobe kicked or thrown violently from the work unit. Various anti-kick backarrangements have been tried without too successful solution.

One of the objects of the present invention' is to provide a radialmachine of this type that is less burdensome to operate.

Another object is to provide a machine that may bey adjusted for itsvarious operations vin a quick and easymanner and cannot be forced outof proper alignment -while makingthe adjustments..

A further object is to provide a machine with safety features that willnot interfere with the normal operation of the machine and will actaffirmatively to protect the operator.

Yetanother objectof the invention is to provide a Yrelatively.inexpensive but accurate machine for precision operation that may beeasilyY manipulated or set up and yet be rugged, safe and stand severehandling by inexperienced operators.

Various other objects of this invention will be pointed out hereinafterwith reference to the.J

drawings wherein an exemplication of anembodiment of the invention isset forth.

In the drawings:

Fig. l is a view in side elevation of one embodiment of the inventionwith the base and legsk not Figs. 5 and 6 are views in top plan andfront elevation respectively of an improved rip lock.

Fig. 7 is a fragmentary View of the upper saw guard locking means.

Fig. 8 is a View of the lower saw guard and rip guard and theirattachment to the upper saw guard which is shown broken away.

Fig. 9 is a bottom plan View of Fig. 8.

Fig. 10 is an enlarged fragmentary view of the right end portion of Fig.9.

Fig. 11 is a view in front elevation'of the rip guard.

Fig. 12 is an enlarged fragmentary view in section through the motorhousing, yoke and journaly lock.

Fig. 13 is a view in side elevation of a fragment of another embodimentof the invention.

As exemplified herein and for simplicity, the invention is disclosed inconnection with a work unit embodying a saw blade. Tools of this typenormally include a work bench (not shown) an upright supporting memberor column andan arm extending radially from the column over the workbench. A work unit is normally associated with the arm and a carryingmember is provided so that the work unit may be moved backwardsl andforwards across the bench in the direction of the length of the arm andradially to and fromv the supporting member by hand operation.v In someembodiments the arm itself is slidable in the carrying member withrespect to the column while in others the unit is slidable with thecarrying member along the arm or a track on the arm to obtain thedesired results.

For precision adjustments these parts are built from relatively heavy,rugged materials such as iron castings and steel rods or bars whichmeans that an operator must overcome a large amount of initial inertiain even the simple operation of cross cutting a board. Prior machineshave tried to overcome this by the use of bearing rollers running on nattracks but guide means were necessarily added to keep the work unit inalignment creating additional friction or the wheels or rollers weremounted at various angles to each other on angularly disposed tracksrequiring extra machining, expense and difficult assembly.

In a preceding Patent No. 2,291,999, in which applicant was a jointinventor, rails having a rectangular cross section were used to form aV-shaped track and bearing rollers having V- shaped annular grooves wereused to intert over this track to hold the carrying member in properalignment, Friction was not entirely overcome however as the outerportion of the grooved rollers travelled faster than the inner portionand some portion of the grooved rollers necessarily was dragged alongthe track.

In the present invention this problem is overcome by causing the rollersand track to be so constructed and arranged as to afford only linecontact between them in lines extending longitudinally of the arm. Therollers may be so arranged that the line contact may form a generallytriangular pattern between opposed rollers adding strength, rigidity andassuring alignment at all times without additional rails, guides orwheels. This may be accomplished by having the rollers meet the track ina generally tangential manner.

For low cost production, a saving of time in making adjustments andsetting up the tool for a new operation is essential since thismanipulation is non-productive work. The present invention incorporatesimprovements in adjusting means to provide quick, easy adjustment of thework unit and the upper saw guard.

The lower safety guard includes a series of links on either side of thesaw blade that offer little resistance to a work piece as the work unitis moved over it and constantly moves in front of the blade to warn acareless operator of the approach of the blade. Since it is mounted oneither side of the blade, the operator has a constant view of the workand cutting line. The links on one side of the blade operateindependently of the links on the other side, as in a mitre or bevelcut, to constantly protect the operator. With former guards, a bevel ormitre cut might protect the operator from one side only, leaving theblade entirely exposed on the other.

When ripping, the upper saw guard normally is swung around so that itjust clears the work piece. The action of the blade picks up the sawdust and carries it out an exhaust opening in the guard to free the workof this dust. As antikick back attachment may be mounted on the upperguard at a point where it will yieldingly drag over the work piece as itis fed through the blade and will positively dig into the work piece andprevent it from being thrown or kicked from the machine by the bladeshould the latter strike a knot in the wood or a too green section.

With reference to the drawings there is shown an upright member I towhich is mounted a Y the upright supporting member I0. The uprightmember is suitably mounted to any well known work table (not shown)whereby a work piece may be brought into proper position for a cuttingoperation by the work unit.

As is customary in machines of this type, the arm I2 may be mounted tothe upright for horizontal swinging movement through 360; the work unitmay be suspended for a horizontal pivot of 360 and the motor unit IB maybe suitably mounted in its yoke for a vertical rotation through 360giving a great amount of exibility to the adjustments of the machine forvarious operations.

With reference to Figs. l, 3 and 4 it will be seen that the arm I2includes a casting 22, generally cylindrical in cross section withspaced bosses 24-24 on diametrically opposite sides which may beaccurately machined to receive the rods or tracks 25 and 26.

At its forward end the casting 22 is provided with a suitable mountingto pivotally receive a yoke 20 in which is journaled a motor I8 throughbearing members 2l, 28. The housing for the motor may be provided with araised annular rib 29 (Fig. l2) which engages the inner surface of theyoke 20 upon proper application of the lever mechanism 30 frictionallyto hold the motor assembly in a predetermined position.

In the embodiment of Fig. 1 the carrying member is pivotally mounted tothe upright member I0 and includes an elongated housing having a bottomportion 32', side members 33 and end members 34 formed to receive theradial arm I2 with its side rails 25, 26.. Preferably there is a re-vmovable top 35 for the housing. Adepending collar 36 may be castintegrally with the bottom 32 to t over the upright member I0 and restupon a fixed collar llthereon so that the arm I2 and its work unit I4may be swung radially of the member I0. A suitable clamping member 31may be mounted with respect to collar 36 and the upright to hold the armI2 in a predetermined position.

The arm I2 is mounted within the carrying housing member I6 throughmeans of pairs of oppositely disposed bearing rollers in rollingengagement with the cylindrical tracks '25, 26. These bearing rollersare rotatively mounted in the side walls 33 and extend over in linecontact and alignment with the track longitudinally of the arm I2.Toward the rear of the housing one pair of oppositely disposed bearingrollers 38 and 39 are shown so constructed and arranged with respect totrack 25 while at the forward end of. and at the same side of thehousing, bearing rollers 4I and 40 are similarly arranged with respectto said track.

Diametrically opposite (Figs. 2, 3, 4) to these pairs are roller pairs42, 43 and 44, 45 correspondingly arranged with respectto track 26. Theupper wheels in the rear 38, and 44 may have a V-shaped rim surfacewhile their respective opposites 39, 45 may have a substantiallycylindrical rim or surface. Conversely the lower rollers in the forwardpart may have a V-shaped surface 46 while their respective opposites 40and 42 may have a cylindrical rim surface. Thus the V-shaped surfacesbear the weight of and guide the arm as it and the work unit are pulledoutwardly from the upright I0 while the cylindrical bearing rollers holdthe arm in proper position.

As may be seen in Fig. 4, the result is that the bearing rollers 42, 43meet the track in a sub stantially tangential contact with a V-shapedroller arranged in opposition to a cylindrical 5. roller whereby toafford line contact between rod 26 and the rollers along a plurality of.lines .extending longitudinally of the arm and arranged in a generallytriangular pattern A. The arm and its track cannot rotate, rock nortwist in this mounting with a proper alignment of the rollers. Werecylindrical rollers arranged in position to each other the arm and trackmight slip sideways in the mounting unless further guide means wereinterposed. The V-shaped wheels furnish this guideway without its addedfriction and retains the line contact.

To the front of the carrying member IB may bemounted a rip lock,generally designated at 48 (Figs. 3, 5 and 6), to hold the work unit I4spaced at a predetermined interval from the upright member li). Asshown, this rip lock includes an upper member generally V-shaped withone leg forming a jaw member 59 and with an elongated fulcrum leg 52 andhaving a screw threaded aperture at its outer end to receive a threadedclamping. thumb screw 54. This upper member is freely pivoted along itsjaw leg 50 as at 56 so that the jaw overlies the track rod 26. Theweight of the fulcrum leg and its Iscrew 54 tend to swing the jaw i!upwardly. A lower member, likewise generally V-shaped, may have a jawleg 58 and a clamping leg 65 and be freely and pivotally mounted throughits apex as at B2 in a spaced but nested relation with the upper memberso that its jaw member underlies the rod 2S and the clamping leg 60 isadjacent the fulcrum leg 52 and its clamping member 54. Jaw 58 tends toswing downwardly from rod 26 from force of gravity bringing leg 6U intocontact with the inner end of screw 54.

Upon tightening screw 54, one of these jaw members mayv come intocontact with rod 26 prior to the other. Further tightening brings theother jaw member into an equalized grip upon the track 26 that cannotdistort nor misalign the track or its arm and does not mar or scratchthe nish. It also forms a quickly operated lock at any predeterminedpoint along the track.

The lever mechanism 3o (Fig. 12) provides a speedy adjustment for thework unit. Since it normally is used more than any other adjustment ittends to wear more rapidly and the operating handle, through wear, mayat times interfere with the work piece or the vision of the Thismechanism provides means for The journal has an interiorly threadedaperture 66-to receive a stripper orvclaniping bolt 61. Upon its innerportion, bolt 6T is threaded to be receivedl in aperture 5S. Centrallythis bolt has an enlarged cylindrical surface shouldered against theouter end of journal 54 and an en'- larged clamping head. In eiect thisbolt forms a continuation of journal member 64, which, eX'- ce'pt forease of machining and assembly, might be formed in this manner withslight changes. Mounted over the cylindrical surface of this bolt andabutting the yoke bearing member is a locking bushing 58 externallythreaded (left handed) to' receive correspondingly internally threadedhandle collar 69 having an operating handle 10 formed as a part thereof.A locking washer 12 is mounted over the stripper bolt between itshead'and the end of the locking bushing 'and is adapted'to abutagainstthehandle collar 69 andy the head of the bolt.

A vflanged portionv 'Il of bushing VF58 Vmay have peripheral openings13- formed therein and the-` yoke bearing member abutting said llangemay` have an adjustment opening 1d therein carrying a dowel pin 15 sothat bushing 68 may be adjusted to and held in -a plurality of positionsaround its mounting over bolt 61 forming means for locking. .saidbushing to the bearing member against rota'Y tion.

In assembly, washer 'l2 is slid overibolt Bland against its head. Collarmember 69 is partially.

screwedover bushing 68 and the bushing slid end of journall 6d. Bushing68 is now turned to a desired adjusted position and locked in place bymeans of a dowel pin l5 in an aperture13 so. that handle member 1U isout of the way ofthe.

operator and rthe work, as for instance as shown in Fig. 3.

Upon rotating handle 'HJ clockwise, it presses against washer 5l and thehead otbolt 61 because of its left hand thread, pulling journal 64 intothe yoke bearing opening 65 untilthe annular rib 29 is intightfrictional contact with yoke 20. A slight counter clockwisemovement of handle 'ill loosens the assembly so that the trunnions andthe work unit are freedfor rotation. Should theY parts wear so thathandle 'l0 hangs downwardly in the way of an operators vision, bushingA623 may be turned so thata new opening i3 is presented to dowel pin 'l5and the handle iiiV brought back to a vdesired position.

With reference-to Fig. 3 it will be noted that thev motor housing IS hasan end bell or protecting shell 8@ through which extends the drivenshaft or arbor 82. Upon this end bell is mounted an upper saw guard 84of the usual arcuate shape,

by means of a split saw guard collar having ther integral upper collarmember 86 (Fig. 7) and a lower collar'member 88 hinged at one end to anend of the upper collar member. The free end of the lower collar memberis anged outwardly as at 95 and is slotted to receive a clamping rod 92.slot may be concave to receive the convex portion of a clamping nut 94screwed up over the threaded lower end of rod 92 in av concaveconvexrelationship.

At itsV upper end rod 32 carries a large thumb.v

knob `Sti and fits loosely within and is suspended from a retaining ring98 (Fig. 3) suitably mounted to the upper portion of guard 85.Preferably the.v

parts are so mounted that rod 92 may be fitted into slotted-harige gaata slight angle to the vertical and be held therein by clamping `nut 95.A straight turn of knob SB permits collar 83 to loosen from a clampedposition on end bell so that the-guard may be rotated to any desiredposition thereon. Nut 94, because if its concavo-convex inter'lt withange 9B may be slightly loosened without having rod 92 drop out of itsslot. A further turn permits the rod to drop out Vof the slot when theinteri'lt is broken and the entire guard may be removed quicklyrandeasily.

A lower safety guard for d saw blade assembly is shown in Figs. l, 8, 9and l0. Gene-rally'this.'

guard includes a plurality of links hingedly mounted or `articulated toeach other and to the upper guard and so arranged and constructed as tohang alongside of and below the lower edgeA The under side of flange Q0adjacent the.

of a circular saw blade to protect an operators hand from a rotatingblade. The links are de signed to yield progressively as the blade ismoved through a work piece and to be positively returned to normal fullguard positions as the blade emerges therefrom.

The end links are semi-circular for most of their length to conform tothe periphery of a saw blade but are curved outwardly `at their outerends to be pivotally mounted in a bracket member |02. This bracketcomprises a flat plate portion |03 mounted to the upper saw guard andhas two depending ears |04 and |05 apertured to receive a hinge pin |06and its spacer sleeve |01 suitably mounted therein. The outwardly curvedportions of the end links are mounted over the hinge pin and spaced fromeach other by the sleeve |01. Over the sleeve |01 a spring member |08may be mounted having free ends |09 and l0 in operative pressing Contactwith spring studs and ||2 respectively mounted on links |00 for thatpurpose. Ear members |04 and |05 have stop members I3 to prevent thelinks from being forced out of operative guard position by spring means|08.

At the inner end of each link |03 is mounted a center link pin H4. Acenter link member ||6, arcuate in shape and following the generalcurvature of the saw blade, is slotted as shown at ||1 and is mountedover the pin lld and suitably held in place for articulated movementbetween the links. In operation, as work unit I4 is advanced to cut awork piece,a portion of an advance link m0 will strike the work pieceand be pivoted inwardly and upwardly around the hinge member |05. At thesame time the central link member will be bent upwardly and inwardlyaround its rear pin and slot arrangement while the forward slot |1 willallow its pin I4 to slide therein permitting this movement. As thecenter link passes over the work piece the rear pin and slot arrangementwill permit the central and rear links to slide smoothly over the workpiece without dragging thereon. Due to its curved formation, the lowerguard will touch or contact the work piece substantially tangentially orat only one point at a time instead of throughout a substantial portionof the work piece.

As the lower guard passes beyond the work piece, springs |08 return thelinks to the normal guard position.

A rip safety guard may be attached to the upper saw guard over the lowerguard plate |03 (Fig. 8) and as shown includes a guard bracket I8 whichmay be positioned between ears |04 and suitably attached through plate|03 into the upper saw guard `.Sl-5. It may be slanted rearwardly toclear the hinge member |06 and have an enlarged lower portion |20 whichmay be bored or drilled to receive a hinge pin |22. Ratchet members |254are pivotally mounted over the hinge pin on either side of the enlargedportion |20 and are yieldngly held in operative position by a ilatspring member |20 that is mounted on the bracket as at |21 and overliesthe ratchet members. The latter terminate in teeth portions |28 adaptedto yieldingly slide over a work piece as it passes beneath in onedirection and `which will dig in and positively hold the work pieceagainst movement in a reverse direction should the saw blade strike aknot or green portion. A stop member |25) may be formed on the ratchetmember and a stop stud |36 mounted on guard brackct H8 to hold the teethin a positive guard position upon a reversal of the work piece.

In practice, the upper saw guard is rotated around its collar 86 untilthe teeth |2X8 are slightly more than in contact with a work piece. Asthe latter is fed beneath the saw from right to left in Fig. 8, theteeth will yield and permit this movement. A reverse movement will causethe teeth to dig in to the work piece due to the action of stop member|29 and stud |30 and hold the piece from being kicked or thrown from thesaw.

In Fig. 13 a modification of the invention is Shown wherein the uprightmember 2|0 supports the radial arm 2|2 rotatively but the latter is heldagainst longitudinal movement. Instead the carrying member 2|6 may bemounted to roll along track 22B and be suitably mounted on arm 2|2 bymeans of roller bearing mountings similar to those described for Fig. 1.A yoke 220 may be pivotally mounted to carry member 2|6 to hold a workunit as heretofore described so that the work unit may be moved radiallytoward and away from the upright member by means of the carrying memberin either embodiment of thc invention Other similar modications of theinvention will be apparent to those skilled in the art from anunderstanding of the specifications and drawings appearing hereinwithout departing from the spirit or scope of the invention.

I claim:

l. In a radial saw of the type characterized by an upright supportingmember, an arm carried by and extending radially with respect to saidmember, a work unit, and a unit carrying member connected with said unitand arm, of means for adjusting said unit toward and away from saidupright supporting member in the direction of the length of said arm,said means including a plurality of rods of substantially circular crosssection secured to and extending longitudinally of said arm at oppositesides ot the same to form a double track, and a plurality of sets ofoppositely disposed rollers of generally V-shaped and generallycylindrical surface formation carried by said supporting member inengagement with said track, with the V- shaped rollers arranged inopposition to the cylindrical rollers, whereby to afford line contactbetween the rods and rollers along a plurality of lines extendinglongitudinally of the arm and arranged in a generally triangularpattern.

2. A radial saw as defined in claim l wherein the V-shaped rollers aredisposed to bear the weight of the arm and work unit in adjusting thesame toward and away from the supporting member.

3. In a radial saw of the type characterized by an upright supportingmember, an arm carried by and extending radially with respect to saidmember, a work unit, and a unit carrying member connected with said unitand arm, of means for adjusting said unit toward and away from saidupright supporting member in the direction of the length of said arm,said means including a plurality of rods of substantially circularcross-section secured to and extending longitudinally of said arm atopposite sides of the same to form a double track, and oppositelydisposed rollers carried by said supporting member in engagement witheach track, some of said rollers being of generally cylindrical surfaceformation and at least one of said rollers being generally V-shaped,whereby to afford line contact betweenthe rods and opposed rollers alonga plurality of lines extending longitudinally of the arm.

HARRY n. WILSON.

REFERENCES CITED The following4 references are of record in the' ille ofthis patent:

UNITED STATES PATENTS Number Number Number Name Date Balsiger et al.June 15, 1937 Disbro Feb. 4, 1941 Gardner" Sept. 30, 1941 Wilson et al.Aug. 4, 1942 Ocenavsek Mar. 2, 1943 Roemer Mar. 7. 1944 Schutz July 4,1944 FOREIGN PATENTS Country Date Great glrtln Oct. 11, 1898 GreatBrltln Dec. 31. 1931 Australia July 3, 1941

